This Order declares that a specified "chemical dosing system, water treatment plant" (comprising pumps, chemical dosers, valves, pipes and fittings, and control modules) is a good to which Item 50 in Part III of Schedule 4 to the Customs Tariff Act 1995 applies. It takes effect from 3 June 2009 and continues until revoked. Who it affects: importers and customs officers — it alters which Schedule 4 tariff item is applied to these goods, changing their customs classification and resulting tariff treatment.